The major objective of the Statistical Center for Pediatric Intergroup Studies is to provide comprehensive and efficient statistical services to clinicians conducting Intergroup Studies in Rhabdomyosarcoma. These services include: review and input concerning biostatistical aspects of all protocols; registration and randomization of patients on study; surveillance, monitoring, storage and processing of data collected during studies; review and evaluation of endpoints and the performance of patients on studies; analyses and reports of ongoing and completed studies; and cooperation with clinical investigators in writing scientific papers and reporting clinical research projects. Continuing statistical services will be provided for the conduct of Intergroup Rhabdomyosarcoma III which began in November, 1984 and 835 eligible patients had been entered as of September, 1988. Some stratifications of patients have been closed and the remaining ones are expected to be closed during 1989 or early 1990. Statistical services will be provided for pilot studies which have been planned to guide Intergroup Rhabdomyosarcoma Study IV, which is expected to open in 1990. Also, analyses and reports will be prepared in cooperation with clinicians to investigate various aspects of completed studies, such as the prognosis of patients in certain primary sites. A repository of data will be maintained for patients entered into completed intergroup studies of Ewing's sarcoma and Hodgkin's disease. Non-metastatic and metastatic Ewing's sarcoma patients were entered into studies that were conducted between 1972 and 1983. Pediatric patients with Hodgkin's disease (Stages I and II) were entered into a clinical study conducted between 1977 and 1981. Data from these studies will be maintained for the purpose of preparing special reports, such as prognostic factors studies and studies of the late effects of therapy.